Sainsbury's said any additional profit it made from selling fuel was reinvested into the business to lower food prices not grow its margins, when asked about the findings of the competition authority's report into fuel prices.

"Any benefit we get from any other part of our business, so whether that's Nectar, Argos, the bank, Tu, Habitat or fuel gets invested right back into food," CEO Simon Roberts told reporters on Tuesday. (Reporting by James Davey, writing by Sarah Young, editing by Paul Sandle)